Antenna release mechanism



Feb. 14, 1961 R. A. MARSH ANTENNA RELEASE MECHANISM 2 Sheets-Sheet 1Filed Jan. 28, 1959 INVENTOR, RICHARD A. MARSH.

Wan/x; Mai/tag? ATTORNEY Feb. 14, 1961 R. A. MARSH 2,972,144

ANTENNA RELEASE MECHANISM Filed Jan. 28, 1959 2 Sheets-Sheet 2 INVENTOR,

RICHARD A. MARSH.

By Max/207mg nr 'omwsx United States Patent l ANTENNA RELEASE MECHANISMRichard A. Marsh, Rochester, N.Y., assignor, by mesne assignments, tothe United States of America as represented by the Secretary of the ArmyFiled Jan. 28, 1959, Ser. No. 789,759

Claims. (Cl. 343-709) This invention relates in general to air-seacommunication systems and is directed in particular to improvements inantenna release mechanisms.

A pulsed homing beacon, when functioning in a complete homing system,provides a homing signal which allows for the locating and recovering ofmissile components by either surface vessels or aircraft. Ordinarily,the beacon operates from a location somewhere at sea slightly above thesurface of the water. The beacon system comprises a transmitter, apop-up antenna, a power pack, and a beacon light. Beacon action isinitiated by a pair of water-activated batteries. The activatedbatteries fire a bellows motor which erects the pop-up antenna andswitches on the power for the transmitter and the beacon light. Thisinvention is limited to the release mechanism used for erecting thepop-up antenna.

Accordingly, it is a general object of this invention to provide anantenna release mechanism capable of operating under .the most severeenvironmental conditions without impairment of its performancecharacteristics.

It is a further object of this invention to provide a release mechanismwhich is simple in construction, which requires relatively few parts andyet is extremely reliable in actual operation.

These and other objects of this invention will be more fully understoodfrom the following detailed description and by reference to theaccompanying drawings, in which like reference characters refer tosimilar parts and in which:

Fig. l is a perspective View of the antenna release mechanism and thebellows motor housing assembly;

Fig. 2 shows the antenna release mechanism in its armed position;

Fig. 3 shows the antenna release mechanism an instant after theenergization of the bellows motor; and

Fig. 4 shows the respective trajectories of the bellows motor housingassembly, the antenna spool and the popup antenna.

In Figures 1 and 2, the water-tight kidney-shaped can 1 houses thetransmitter, the transmitter power supply and the beacon light batterysupply (not shown). The flexible antenna 7 and the antenna releasemechanism are mounted on the walls of the enclosure 8, as shown.

The bellows motor housing assembly 2 consists of the motor housing 9,the explosive bellows motor 10, the water activated cells 11 and themoving guide 12, as shown. The motor housing assembly 2 slides sunglyinto the fixed guide 3 and is held securely in position by the triggerrelease spring 13. The antenna is fixedly secured at one end thereof tothe antenna mount 5, the other end being wound around the core of theantenna spool 4. Each of the outer and the inner flanges 20 and 14 ofthe spool have a pair of lugs 15 and 16. The left hand lugs are securelyheld in position by notches 17 of the antenna mount 5; similarly theright hand lugs fit snugly into notches 18 of the moving guide 12.

In operation, each of the two parallel connected cells ice 11 produces1.5 volts when activated by water, the resulting current of which firesthe bellows motor 10. The motor contains explosive elements such as adry load of approximately mg. of an intimate mixture of 50/50 blackpowder and lead mononitro resorcinate. The electrical resistance of thebellows motor igniter is such that the firing current from the wateractivated cells, which are galvanically connected to the input terminalsof the motor, is limited to less than 50 microamperes, although anyother value of current could be used, if desired. Gas resulting from theexplosion expands bellows 21. The action of the bellows motor is veryrapid and powerful (approximately 40 pound thrust).

The initial extension of the bellows depresses the trigger releasespring 13 and releases the motor housing assembly 2 as shown in Fig. 3.Continued extension of the bellows motor forces the motor housingassembly up along the fixed guide 3 and ejects the motor housingassembly, thereby freeing the antenna from the antenna spool, as clearlyshown in Fig. 4. Movement of the motor housing assembly up along thefixed guide also releases the switch spring 19 which energizes thetransmitter and the beacon light 6 in housing 1. After a smallwarming-up period the pulsed homing beacon provides a homing signal forlocating and recovering of the accompanying missile or other components.

The flexible antenna 7, is a laminated assembly. Each of the six laminaeis a length of /z wide spring steel strip stock slightly curved aboutits longitudinal center line (similar to the stock used in flexiblesteel measuring tapes). The laminae are prevented from separating byrivets installed through slots in the laminae. Slots are used to permitrelative longitudinal movement of the laminae during coiling of theantenna. The outside lamina terminates in a clip that is used to anchorthe antenna on the core of the antenna spool 4.

While this invention has been described in conjunction with presentpreferred embodiments thereof, it should be apparent that the inventionis not limited thereto.

What is claimed is:

l. A signalling device for indicating the location of submergedcomponents, comprising a housing, an antenna mount within said housing,a spool having a core and two flanges, a pair of diametrically opposedlugs on each of said flanges, one pair of longitudinally opposed lugsdetachably engaging said antenna mount, a flexible antenna having twoends, one of said ends being fixedly secured to said antenna mount, theother of said ends being releasably wound on said core; apositive-ejection mechanism, and means for detachably securing the otherpair of said lugs to said mechanism.

2. The device of claim 1, wherein said ejecting mechanism comprises anexplosive bellows motor including water activated means for firing saidmotor and thereby erecting said antenna in a generally upward position.

3. The device of claim 2, wherein said water activated means includes atleast one voltage producing cell galvanically connected to said bellowsmotor.

4. A signalling device for indicating the location of submergedcomponents, comprising a buoyant housing, a flexible antenna having twoends, means for fixedly securing one of said ends to said housing, aspool having a core and two flanges releasably mounted within saidhousing; the other of said ends being wound around said core; and meansfor forcibly ejecting said flanges and thereby freeing said other ofsaid ends from the core of said spool and erecting said antenna in agenerally upward position.

5. In a transmitter signalling device comprising a housing, an antennamount fixedly secured to said housing, a flexible laminated antennahaving two ends, a spool having a core and two flanges, a pair ofdiametrically opposed lugs on each flange, a Water-actuated ejectingmechanism, means including a trigger release spring for detachablyretaining said ejecting mechanism to said housing in the absence ofWater penetrating said mechanism; means for fixedly securing one end ofsaid antenna to said antenna mount, the other end of said antenna beingWound around said core; means for detachably retaining one pair oflongitudinally opposed lugs to said antenna mount, means for detachablysecuring the other pair of said lugs to said ejecting mechanism, andmeans including a bellows motor and a current producing cell Within saidejecting mechanism for releasing said trigger release spring upon theentry of water into said cell 4 and for forcibly ejecting said spool andupwardly unwinding said flexible antenna;

References Cited in the file of this patent UNITED STATES PATENTS1,481,605 Hayes Jan. 22, 1924 2,473,050 Camp June 14, 1949 2,528,799Strong Nov. 7, 1950 2,593,432 Freas Apr. 22, 1952 2,675,568 King Apr.20, 1954 FOREIGN PATENTS 526,629 Canada V June 6, 1956

